Hidayat, Taufiq; Henao, Hector M.; Hayes, Peter C.; Jak, Evgueni (2013). The pseudo-binary phase diagrams in the Cu-O-Si system in equilibrium with air and metallic copper have been constructed. Equilibration at high temperature in an appropriate containment material, followed by rapid quenching and measurement of phase compositions using an electron probe x-ray microanalysis (EPMA) technique, was carried out to obtain the phase equilibria data. The investigation has been extended to characterize the effects of CaO, MgO, AlO, and ‘‘FeO’’ on the liquidus isotherms of tridymite in equilibrium with metallic copper at temperatures of 1473 K and 1573 K (1200 °C and 1300 °C).

Jak, Evgueni; Hayes, Peter (2012). It is widely recognized that alkali metals, such as, potassium and sodium can cause operational problems in the iron blast furnace. These elements can influence properties, such as, the softening and melting of ores, formation of scaffolds, coke properties, and refractory life. It has been established that recirculation of these elements occurs within the furnace. In the lower furnace vaporization occurs in the high temperature hearth and bosch regions, and condensation occurs in the upper furnace below or in the cohesive zone. For these reasons the input of alkalis into the furnace is strictly controlled. Optimized thermodynamic databases describing slags in the system Al2O3-CaO-FeO-Fe2O3-Na2O-K2O-MgO-SiO2 have been developed and, combined with the computer software FactSage; these databases have been used to predict the possible behaviour of alkalis in the blast furnace and to examine the effects of changing process variables on reactor performance. To demonstrate this approach to process modeling the furnace is considered as a two-stage equilibrium reaction system and the results of initial analysis are reported.

Ilyushechkin, Alexander Y.; Dolan, Michael; Dave, Narendra; Hayes, Peter C.; Jak, Eugene (2012). Experimental methods, based on electromagnetic levitation, have been developed for preparation and investigation of copper-rich alloys, and for the determination of oxide-metal phase equilibria. These techniques involve high-temperature equilibration, rapid quenching and chemical analysis of the phases using electron probe X-ray microanalysis. The experiments can be carried out in the temperature range 1373-1873 K (= 1100 degrees C-1600 degrees C). A developed calibration method, using phase equilibria data in known oxide systems, was applied for pyrometric temperature measurements. Described methods of the application of the electro-magnetic levitations were used for in-situ formation of Cu-based alloys and for formation of Ca-ferrite slags equilibrated with metallic copper.